The use of cone-beam computed tomography (CBCT) has expanded the field of oral and maxillofacial radiology and with commercially available machines appearing in dental practices The American Dental Association (ADA) has just published an advisory statement in the Journal of the American Dental Association.

The key element of the statement is captured in the practical implications in the abstract, which states: –

CBCT imaging should be used only after a review of the patient’s health and imaging history and the completion of a thorough clinical examination. Dental practitioners should prescribe CBCT imaging only when they expect that the diagnostic yield will benefit patient care, enhance patient safety or improve clinical outcomes significantly.

As they note CBCT units give a higher radiation dose that traditional dental radiographs. The UK Health Protection Agency gave the range for a typical effective patients dose from a small field of view CBCT machine as 48-652 microsieverts, this compares to 24 microsieverts for a panoramic film. This is between 2 and 27 times more.

A European Project, SEDENTEXCT undertook and evidence-based review of this area and a number of European National Guidance documents have been produced which take these into account and are available on their website.

Derek Richards is the Director of the Centre for Evidence-based Dentistry, Editor of the Evidence-based Dentistry Journal, Consultant in Dental Public Health with Forth Valley Health Board and Honorary Senior Lecturer at Dundee & Glasgow Dental Schools. He helped to establish both the Centre for Evidence-based Dentistry and the Evidence-based Dentistry Journal. He has been involved with teaching EBD and a wide range of evidence-based initiatives both nationally and internationally since 1994.